1. Field of the Invention
The present invention relates to a medical retainer and, in particular, to a medical retainer capable of independently controlling the supply of air and water to hollow organs such as a stomach and a lumen of a small intestine. Also, the present invention relates to a medical operation using the medical retainer.
2. Description of the Related Art
Laparoscopic instruments are routinely used to perform surgery on organs accessible via the abdominal cavity. In order to perform such surgery, it is necessary to expand the space within the lumen of abdominal cavity to allow for the observation of abdominal organs and the manipulation of laparoscopic surgical instruments. A common method of expanding the lumen of the abdominal cavity is to insufflate this space with pressurized gas. Air, carbon dioxide and nitrous oxide have all been used. The insufflation of gas into the space of the abdominal cavity separates the patient's abdominal wall from the organs beneath it, thus creating a working space between the abdominal wall and the organs within the abdominal cavity.
Transgastric endoscopic procedures are being developed as an alternative endoscopic means of operating within the lumen of the abdominal cavity. With this surgical approach, a flexible endoscope is passed through the patient's mouth and esophagus into the patient's stomach. An incision or opening is then made in the wall of the stomach, through which the endoscope may be passed out of the stomach into the abdominal cavity. Instruments passed through this transgastrically placed endoscope are then able to perform surgery on abdominal organs in a manner similar to laparoscopic instrumentation.
A current problem of transgastric endoscopic procedures is the inability to independently control insufflation of the stomach, the small intestine, and the lumen of the abdominal cavity.
When the endoscopic procedure is first started, it is desirable to insufflate the stomach in order to expand it, to flatten out the folds of the stomach and to create a working space within the stomach. A clear view of the stomach wall and a substantial working space within the stomach is necessary to facilitate the next step, which is to endoscopically incise the wall of the stomach. The purpose of creating an incision in the wall of the stomach is to create an opening that will allow the distal end of the endoscope to pass from the stomach into the abdominal cavity.
Once the endoscope enters the abdominal cavity, it is desirable to contract the stomach and insufflate the abdominal cavity. Insufflating the abdominal cavity creates a large working space for the flexible endoscope to observe and perform surgery on the abdominal organs. After entering the lumen of the abdominal cavity, it is advantageous to remove the excess gas previously added to the stomach in order to reduce the size of the stomach, and thereby reduce its protrusion into the lumen of the abdominal cavity. In addition, since the stomach communicates with the small intestine via the pylorus, pressurized gas within the stomach will flow into the small intestine, pressurizing the intestines as well. The gas flowing into the small intestine will expand the intestines, causing them to project into the abdominal cavity, further reducing the available working space within the abdominal cavity.